Morphological basis for a mechanical linkage in otolithic receptor transduction in the frog.
Observations made with a scanning electron microscope confirm the binding of the stereocilia to a matchhead-like bulbous terminal at the apex of the kinocilium in frog saccular receptor cells. Since the kinocilium is shown to rest on a portion of the receptor cell that lacks the rigid cuticular base of the stereocilia, movenment of the ciliary ensemble results in a "plunging-like" effect of the kinocilium which produces a distension of the membranc at its base. This membrane distension is envisaged as bringing about the ionic conductance changes necessary for the production of a generator potential and, thus, for the transduction of movement into vestibular nerve activity.
D000818:Animals; D001001:Anura; D007758:Ear, Inner / Q000033:anatomy & histology* / Q000294:innervation / Q000502:physiology; D008855:Microscopy, Electron, Scanning; D011892:Rana catesbeiana; D011984:Sensory Receptor Cells / Q000033:anatomy & histology / Q000502:physiology